Internal combustion engine



Patented Jan. 1940 I George Stephen Kammer, Budapest, Hungary Application June 2'7, 1938, Serial No. 216,089 In Germany May 25, 1938 5Claims.

The invention relates to internal combustion engines of the kind having a separate'combustion chamber in which the fuel and air mixture is formed.

In the known engines of this type the fuel supply is efiected slowly and extends generally over about 30 of crank movement, so that. the combustion has already long commenced while fuel is still beingsupplied and usually even before half the fuel for one stroke has entered. The effect of this kind of fuel supply is a gradual increase of the, combustion pressure but it must also be admitted that very high air consumption is necessary to achieve on one hand complete combustion and on the other admissible exhaust temperatures, for the combustion spread over a considerable part of the working stroke results the cylinder is so regulated. by the controlled member that undesirably high pressures do not occur in the working cylinder space. According to the present invention the variations of cross-sectional area of the connecting passage or passages are carried out not by an externally controlled member, but automatically. Moreover, the contents of the combustion chamber are caused to eddy in several directions.

According to the invention the working piston is provided with one or more throttling elements adjustable in dependence on the speed of the engine, which enter one or more of the stationary connecting passages between the working cylinder space and the combustion chamber when the working'piston is in the neighborhood of its necting passage is thus reduced by the cross section of the throttling element which has entered it or is even closed completely, and is then gradually opened during the working stroke, so that the desired pressure is maintained in the working cylinder.

The throttling element may be rotatable or movable lengthwise; the transfer cross-sectional area variesin accordance with the extent of this movement. I

The combustion chamber is advantageously in the shape of a sphere or an ellipsoid of revolution, and if it is connected to the working cylinder space by several passages, a group of the latter may remain unthrottled but should have 5 small cross sections in comparison with that of the'throttled passages. The air flowing into the combustion chamber through these passages during compression has a favorable effect on the mixing due to eddying. It is advisable to arrange 10 the longitudinal centre lines of the connecting passages tangential to the wall surface of the combustion chamber and so.to place them. in relation to each other that the jets of air entering the combustion chamber by these passages pro- 15 duce eddying movements in different planes, for instance in two planesbeing at right angles to each other.

In the passages with uncontrolled cross-section or in only one of them non-return valves 20 such as ball valves may be provided which open towards the combustion chamber so that a larger cross-section is available for the entry of air into the combustion chamber, while the high pressure products of combustion can only pass 25 to the working cylinder space through the passages. with controlled cross-section.

The whole quantity of fuel for one stroke is introduced into the combustion chamber in a shorter time than would correspond to the spe- 3o cific retardation of ignition, that is the retardae tion corresponding to the speed of the engine. In this way a sudden. combustion of the whole quantity of fuel for one stroke is achieved with the maximum increase of pressure and tempera- 35 ture,- provided the formation of the mixture has taken place. in the manner. intended, which is ensured by the present invention.

' The advance of injection should be so chosen thatthe explosive increase of pressure is como pleted at the latest when the crank has passed the upper dead centre by 4' to 5, so that the expension and fall of temperature can commence "immediately thereafter.

It may be seen from what-has been stated that 5 the invention allows of obtaining the following advantages: an approximately constant volume combustion in the combustionchamber, an earlier start. of expansion and its beginning at a higher pressure, and a highertemperature difference of 50 the process.

A constructional form of the engine according to the invention is shown by way of example in the drawing, but for the sake of simplicity with only two transfer passages. In the drawing Figure 1 is a section taken through the axis of the cylinder.

Figure 2 is a section through the combustion chamber on the line 11-11 of Figure 1.

Figure 3 is a section on the line III-III of Figure 2.

Figure 4 is a view of a form of control for the throttling element for a large range of speed.

Figure 5 is a detail plan view partly in section.

Figure 6 is a section of a modified form of the cylinder head and combustion chamber.

A cylindrical plunger I is mounted in the piston 2 so as to be rotatable and is supported on the conical seating 3 screwed into an extension 4 which is cast with the piston. The end of the plunger I projecting from the piston 2 is made conical and is provided with a groove 5 commencing at the upper face of the piston and adapted to cooperate with a groove 8 formed in the passage I when the'engine is running at high speeds. The cylinder 9 is provided with a cylinder head 8, which contains the combustion chamber ID, and the fuel nozzle II terminates in the latter. Communication between the working space of the cylinder I and the combustion chamber III is by means of the passage I and in addition a small passage I2, which for the purpose of air supply to the combustion chamber terminates therein in a different direction. The arrangement of the passages can bebetter seen from Figure 3. The plunger I has at its end projecting below the piston 2 an arm I3. The gudgeon pin is omitted for the sake of clarity.

As the piston 2 approaches the cylinder head 8 (lining the compression stroke, the plunger I enters the passage I, first with its conical end, and throttles the flow of air' passing therethrough from the cylinder space to the combustion chamber III. The conicalpart of the plunger I does not extend as far as the piston face but the plunger has above the piston face 'a free cylindrical part on which the groove 5 is formed. This groove is intended to come more into register with the groove 6 by rotation of the plunger I as the engine speed increases so as to reduce progressively the throttling of the passage I. It is also possible to provide several grooves like 5 with corresponding grooves like 8 to cooperate therewith.

The air fiow is thus more and more throttled as the piston approaches its upper dead centre and is finally confined substantially to the small cross-section of the passage I2.. If the latter is omitted a suitable clearance should be left between the *-diameter of the plunger I and the bore of the passage I.

Combustion proceeds now in the manner described and is complete shortly after the piston has passed its upper dead centre. Hereupon the piston, together with its associated parts, commences the working stroke.

Figure 2 shows in section the groove 6 formed in the wall of the combustion chamber III. The plunger I with its conical end is visible in plan. The groove 5 ,drawn in dotted line is in the position for high speed. If the arm I! (Fig. l) is swivelled about the axis of the plunger I the register of the grooves 5 and 6 is gradually reduced and the throttling is increased. It will further be seen that the air fiow from the passage I2 will impart to the air eddy produced by the air flowing in from the passage 1 a rotation about an axis normal to the axis of said eddy.

In Figure 4 the piston 2 has almost arrived at its lower dead centre; If the speed has diminished the plunger I should be rotated and with it the groove 5 so as to reduce'the throttlin cross-section. For this purpose a fork I4 is provided which is pivoted on a stationary pin I5 and is attached to an arm I6 located at the other end of the pin. The fork I4 is placed inside the cylinder 9, while the pin I5 projects through the cylinder wall 8. The arm I8 located outside the cylinder is connected to a suitable governor.

The fork I4 is so placed that its throat is almost or fully entered by the arm I 3 at the lower dead centre of the piston 2. If the fork has been moved it will push the arm I3 out of its position, so that the throttling in the passage 1 is varied. It may be remarked that the piston speed is already small here and that any actuation of the fork I only comes into question when there is a change of speed.

In the modification shown in Fig. 6 the passage I2 is provided with a ball-valve I1 so arranged that. it gives the passage free for the air which flows from the cylinder 9 into the chamber III but closes it for the combustion gases coming from the chamber I0 so that these gases can only enter the cylinder 9 through the passage I the cross section of which is being controlled by the plunger I.

' To prevent any accidental rotation of the plunger I a spring I8 may be provided at a suitable place, being secured for instance to the bottom of the extension 4 as shown in Figures 1-4 and 5, and being pressed against the nave of the arm I3 embracing theplunger I. The friction arising between the spring I8 and the nave of the arm I3 will prevent any undesired rotation of the plunger I.

I claim:

1. An internal combustion engine comprising in combination a working cylinder, a combustion chamber separate therefrom but connected to it by at least one passage, a fuel nozzle terminating in the combustion chamber, a piston operating within the cylinder, an adjustable member mounted on the piston and entering the passage communicating with the combustion chamber so as to throttle this passage when the piston is at its inner dead centre and to release such throttling at a predetermined rate when the piston is moving away from said dead centre, and speed responsive means for varying the position of the adjustable member to increase the area of the throttled passage witl' 'ncreases in the engine speed and vice versa.

2. An internal combustion engine comprising in combination a working cylinder, a combustion chamber separate therefrom but connected to it by at least one passage provided with a groove opening into the combustion chamber, a fuel nozzle terminating in the combustion chamber, a piston operating within the cylinder, a plunger rotatably mounted in the piston with its end projecting beyond the piston face to enter the passage communicating with the combustion chamber, the plunger having a lateral groove to cooperate with the groove in said passages, and speed responsive means for rotating the plunger to increase the area of register between the respective grooves with increases in the engine. speed and vice versa.

3. An internal combustion engine comprising in combination a working cylinder, a combustion chamber separate therefrom but connected to it by at least one passage provided with a groove opening into the combustion chamber, a fuel nozzle terminating in the combustion chamber,

a piston operating within the cylinder, a plunger rotatably mounted in the piston with one end projecting beyond the piston face to enter the passage communicating with the combustion chamber, the plunger being tapered at said one end and a lateral groove to cooperate with the groove in the passage to the combustion chamber, an arm mounted on the other end of the plunger, a fork located to be entered by the arm at the outer dead centre of the piston, and speed responsive means for moving the fork in dependence on the engine speed and thus rotate the plunger to increase the area 01' register between the respective grooves with increases in the engine speed and vice versa.

a 4. An internal combustion engine-as in claim 1 with at least two connecting passages between working cylinder and combustion chamber, said passages terminating in the combustion chamber tangential with respect to the walls of said chamber in different radial planes.

5. An internal combustion engine comprising i in combination a working cylinder, a combustion chamber separate therefrom but connected to it by at least two passages, a fuel nozzle terminating in the combustion chamber, a piston operating within the cylinder, an adjustable 'member mounted on the piston and enteringone of the passages communicating with the combustion chamber so as to throttle this passage when the piston is at its inner dead centre and to elease such throttling at a predetermined rate when the piston is moving away from said dead centre, means for varying the position of the adjustable member to increase the area of the throttled passage with increases in the engine speed, and vice versa,'and a non-return valve in at least one other passage to permit flow from the cylinder to the combustion chamber but not in the reverse direction.

GEORGE STEPHEN gamma. 

